1. Field of the Invention
The present invention relates to electronic chip modules, and more particularly, to an electronic chip module that can improve heat dissipation.
2. Description of the Related Art
Recently, the use of electronic components, such as integrated circuits (ICs), improves convenience and leads to a reduction in size, weight, and thickness of electronics, such as cellular phones or personal digital assistants (PDAs).
In order to achieve the reduction in size, weight, and thickness of the electronics, the electronic components need to be reduced in size, weight, and thickness, and a multi-chip module having these electronic components mounted therein also needs to be reduced in size, weight, and thickness. Therefore, a heat dissipation mechanism of the entire multi-chip module is a major consideration when achieving the reduction in size, weight, and thickness of the entire multi-chip module mounted with the electronic components.
That is, since heat-generating devices, such as a power module and an IC chip, produce high temperature heat, thermal dissipation units, such as heat sinks, are used to prevent malfunction of the electronics. This heat sink is attached to a rear surface of a board onto which wires connected to the multi-chip module are printed.
The board has a plurality of heat-generating devices mounted on a major surface, a plurality of thermal vias provided at positions of the board where the heat-generating devices are mounted, and a heat sink provided on another major surface opposite to the one major surface with a resin layer interposed therebetween. The heat sink dissipates heat through the thermal vias. Further, heat dissipation efficiency is increased by using a board formed of ceramic or alumina with high thermal conductivity.
However, when heat generated from the heat-generating devices is transmitted to the board, the resin layer, and the heat sink, the thermal conductivity is significantly reduced since the individual components are formed of different materials from each other. Particularly, the resin layer used to bond the heat sink to the board onto which the wires are printed causes a significant reduction in thermal conductivity while the heat is transferred from the board to the heat sink. That is, thermal loss occurs. Therefore, the above-described thermal dissipation mechanism cannot be expected to provide sufficient heat dissipation because of poor heat dissipation of thermal resin.